package com.ag.admin.web.servlet;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.ag.admin.utils.UserUtil;

/**
 * 随机图片生成器 Servlet
 * 
 * @author 黎肇明
 * 
 */
public class ImageCodeMakerServlet extends HttpServlet {
	private static final long serialVersionUID = -3450527822332135839L;

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		doPost(req, resp);
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		resp.setHeader("Pragma", "No-cache");
		resp.setHeader("Cache-Control", "no-cache");
		resp.setDateHeader("Expires", 0);
		int width = 90, height = 40;
		BufferedImage image = new BufferedImage(width, height,
				BufferedImage.TYPE_INT_RGB);
		Graphics g = image.createGraphics();
		Random random = new Random();
		g.setColor(getRandColor(180, 250));
		g.fillRect(0, 0, width, height);
		for (int i = 0; i < 5; i++) {
			g.setColor(getRandColor(180, 255));
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			g.drawOval(x, y, 4, 4);
		}
		g.setFont(new Font("", Font.PLAIN, 40));
		String sRand = "";
		for (int i = 0; i < 4; i++) {
			String rand = String.valueOf(random.nextInt(10));
			sRand += rand;
			g.setColor(new Color(20 + random.nextInt(80), 20 + random
					.nextInt(100), 20 + random.nextInt(90)));
			g.drawString(rand, (17 + random.nextInt(3)) * i, 34);
			for (int k = 0; k < 12; k++) {
				int x = random.nextInt(width);
				int y = random.nextInt(height);
				int x1 = random.nextInt(9);
				int y1 = random.nextInt(9);
				g.drawLine(x, y, x + x1, y + y1);
			}
		}
		req.getSession().setAttribute(UserUtil.VERIFY_CODE, sRand);
//		System.out.println("req.getSession().getAttribute(UserUtil.VERIFY_CODE)"+req.getSession().getAttribute(UserUtil.VERIFY_CODE));
		g.dispose();
		ImageIO.write(image, "JPEG", resp.getOutputStream());
	}

	private Color getRandColor(int fc, int bc) {
		Random random = new Random();
		if (fc > 255) {
			fc = 255;
		}
		if (bc > 255) {
			bc = 255;
		}
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}

}
